This application makes reference to, incorporates the same herein, and claims all benefits accruing under 35 U.S.C. xc2xa7119 from an application for A METHOD FOR CORRECTING PRINTING ERRORS IN A SHUTTLE TYPE OF A MULTIFUNCTIONAL APPARATUS earlier filed in the Korean Industrial Property Office on the 6th of November 1997 and there duly assigned Serial No. 58305/1997.
1. Field of the Invention
The present invention relates to a technique for correcting printing errors in a shuttle type multifunctional apparatus, and more particularly to a technique for correcting printing errors in a shuttle type multifunctional apparatus, in which it is possible to correct printing errors, such as overlaps and spacing errors, which are generated between bands of a printer block.
2. Description of the Related Art
Generally, office automation apparatus, such as a printer, a copier, a computer, a facsimile device, and a scanner, are independently utilized. Recently, with the development and a popularization of office automation apparatus, a multifunctional office automation apparatus has been proposed, which is capable of carrying out various functions. A multifunctional apparatus is defined as follows:
First, it means an apparatus, including a printer, a facsimile device, and a copier, for example, which are integrated with one another so as to perform two or more functions. Second, it means an apparatus, including a printer, a facsimile device, and a copier, for example, which cooperates with a computer so as to perform new and various functions.
In a shuttle type of multifunctional apparatus according to the related art, a scanner and a printer head are mounted on a horizontal shaft and reciprocated by means of a carriage return motor. A document to be scanned or a paper to be printed is moved at a constant velocity by means of a line feeding motor.
In a case of performing printing using the multifunctional apparatus according to the related art, bands of printing blocks are spaced from each other or overlapped with each other due to the mechanical tolerances of the multifunctional apparatus, especially the mechanical tolerance of the line feeding motor.
In order to removing printing errors such as spacing errors or overlapping of the bands of the printing blocks, therefore, the multifunctional apparatus is repeatedly subjected to a test for measuring the printing errors. Specific data are obtained by the test, and then a corrected value is calculated by adding or subtracting to/from a moving distance of a paper corresponding to a rotational velocity of the line feeding motor with reference to the specific data.
Furthermore, each corrected value is calculated to be in correspondence with each specific data with respect to a plurality of multifunctional apparatus. Then, a corrected average value is calculated and supplied to the multifunctional apparatus.
I have noticed that according to the method for correcting the printing errors in the multifunctional apparatus of the related art, however, since the corrected value must be calculated by using the specific data, the multifunctional apparatus is repeatedly subjected to the test for measuring the specific data. This is, in my opinion, a disadvantage in that the efficiency of operations is degraded.
Furthermore, since the plurality of the multifunctional apparatus are subjected to the test for measuring the printing errors and the specific data are detected from the multifunctional apparatus, the multifunctional apparatus have a different specific error even though the corrected optimum value is obtained by calculating the corrected value corresponding to the specific data and supplied to the multifunctional apparatus. Accordingly, I have found that an optimum quality of the printing cannot be obtained.
The following patents each discloses features in common with the present invention: U.S. Pat. No. 5,661,788 to Chin, entitled Method And System For Selectively Alerting User And Answering Preferred Telephone Calls, and U.S. Pat. No. 5,524,140 to Klausner et al., entitled Telephone Answering Device Linking Displayed Data With Recorded Audio Message.
The present invention has been made to overcome the above described problem of the related art.
It is an object of the present invention to provide on improved technique and apparatus for correcting printing errors.
It is another object to provide a technique and apparatus for correcting printing errors in a multifunctional apparatus, in which a preset reference pattern is printed, the printing errors are detected by scanning the printed reference pattern, and finally the printed errors are corrected, by means of a program applicable to all kinds of multifunctional apparatus.
To accomplish these and other objects of the present invention, there is provided a method and apparatus for correcting printing errors in a shuttle type multifunctional apparatus which includes a scanner module reciprocated along a horizontal axis and an electric line feeding motor capable of moving a shuttle type printer head and documents a predetermined distance, byprinting a preset reference pattern when a correcting mode for correcting printing errors is set; detecting numbers of dots corresponding to the printing errors by comparing a scanned pattern with the reference pattern after scanning the printed reference pattern; calculating a printing error value by using the number of dots corresponding to the printing errors detected in the detecting step and obtaining a correcting value by adding and subtracting the error value to and from a space between adjacent bands; storing the correcting value obtained in the calculating step; and controlling the space between adjacent bands according to the correcting value. In the calculating step, the calculation is performed by adding and subtracting the value of the errors to and from a distance at which the electric line feeding motor moves. In the controlling step, the moving distance of the electric line feeding motor is controlled according to the correcting value. The reference pattern may include first and second patterns having a predetermined length in a vertical direction, which are set to be eccentric to each other.
In the detecting step, the number of detected dots which are in correspondence with a distance between a lower end of the first pattern and an upper end of the second pattern of the scanned pattern. The distance is calculated by using a first group of dots having black data detected due to the second pattern until the lower end of the first pattern is scanned and a second group of dots having white data detected until scanning the lower end of the first pattern to the upper end of the second pattern. In the calculating step, when the first group of dots are detected, the correcting value is calculated by using a formula as follows:
(numbers of nozzles per a printing block/a resolution of a printer head)+(number of dots in printing errors/a resolution of a shuttle type scanning head)inch.
In the calculating step, when the second group of dots are detected, the correcting value is calculated by using a formula as follows:
(numbers of nozzles per a printing block/a resolution of a printer head)xe2x88x92(number of dots in printing errors/a resolution of a shuttle type scanning head)inch.